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IMGT reference sequences in FASTA format:

Amino acid sequences without gaps

The FASTA header contains:
IMGT accession number | gene and allele name | species | functionality | exon name | domain name | domain type | alternative splicing (if it is) | partial (if it is) 
>AY322147|B7H4*01|Mus musculus|F|EX1|
MASLGQIIFWS
>AY322147|B7H4*01|Mus musculus|F|EX2|
IINIIIILAGAIALIIGFGIS
>AY322147|B7H4*01|Mus musculus|F|EX3|[D1]|V-LIKE|
GKHFITVTTFTSAGNIGEDGTLSCTFEPDIKLNGIVIQWLKEGIKGLVHEFKEGKDDLSQ
QHEMFRGRTAVFADQVVVGNASLRLKNVQLTDAGTYTCYIRTSKGKGNANLEYKTG
>AY322147|B7H4*01|Mus musculus|F|EX4|[D2]|C-LIKE|
AFSMPEINVDYNASSESLRCEAPRWFPQPTVAWASQVDQGANFSEVSNTSFELNSENVTM
KVVSVLYNVTINNTYSCMIENDIAKATGDIKVT
>AY322147|B7H4*01|Mus musculus|F|EX5|
DSEVKRRSQLQLLNSGPSPCVFSSAFAAGWALLSLSCCLMLR
>B7H4*01|Mus musculus|F|EX1-EX5|Splicing A|complete|
MASLGQIIFWSIINIIIILAGAIALIIGFGISGKHFITVTTFTSAGNIGEDGTLSCTFEP
DIKLNGIVIQWLKEGIKGLVHEFKEGKDDLSQQHEMFRGRTAVFADQVVVGNASLRLKNV
QLTDAGTYTCYIRTSKGKGNANLEYKTGAFSMPEINVDYNASSESLRCEAPRWFPQPTVA
WASQVDQGANFSEVSNTSFELNSENVTMKVVSVLYNVTINNTYSCMIENDIAKATGDIKV
TDSEVKRRSQLQLLNSGPSPCVFSSAFAAGWALLSLSCCLMLR*